President Barack Obama and a bipartisan group of senators have said that a path to citizenship for undocumented immigrants should be an essential part of any immigration reform bill. But a hearing in the House of Representatives on Tuesday indicated that some leading Republicans are still unsure whether to support such a proposal.

The hearing, held by the House Judiciary Committee, touched on issues like increased visas for workers in fields like science and technology, as well as whether the U.S. should adopt some type of mandatory system to make sure workers are legally eligible to work.

But one of the clearest points of contention on immigration reform came between Rep. Bob Goodlatte (R-Va.), the chairman of the committee, and San Antonio Mayor Julián Castro (D), who testified at the hearing as an expert.

"Are there options that we should consider between the extremes of mass deportation and a pathway to citizenship for those not lawfully present in the United States?" Goodlatte asked Castro.

"Well, let me say this. I do believe that a pathway to citizenship should be the option for Congress," Castro said. "I don't see that as an extreme option."

Castro continued: "I would disagree with the categorization of that as the extreme. The extreme, I would say, just to fill that out, would be open borders."

Another expert witness at the hearing, tech entrepreneur Vivek Wadhwa, suggested that some sort of indefinite permanent resident status for qualifying immigrants might be an option.

"Without calling them citizens, there is a way," he said.

Prominent Republicans have spoken about the need for the party to embrace a new strategy on immigration. But while some Senate leaders, like Marco Rubio (R-Fla.), support a pathway to citizenship, key House Republicans like Goodlatte, Rep. Lamar Smith (R-Texas) and Rep. Trey Gowdy (R-S.C.) repeatedly questioned Castro about whether he might back some sort of legal status without the possibility of citizenship.

The bulk of the hearing dealt with how to rework the legal immigration system, including one area where Republicans and Democrats already have common ground: the addition of more visas for graduates in the fields of science, technology, engineering and math (STEM). Despite that common ground, partisan division could surface over whether such visas should be added to present-day quotas or be swapped out for existing family-based visas.

One of the most dramatic moments came several hours into the hearing, after a speech by Rep. Luis Gutiérrez (D-Ill.) about the economic and social contributions of young undocumented immigrants who now have legal status under a federal program started last year.

After Gutiérrez spoke, a row of young people stood up and shouted "no more deportations," before breaking into a refrain of "undocumented and unafraid" as security quickly escorted them from the room (see a photo here).

"That was not a good exit point to the excellent points made by the gentleman from Illinois," Goodlatte said. "The way to resolve this is in discussion and careful deliberation about the issues, not by disrupting...members of this committee."

Meanwhile, the second-highest ranking member of the GOP made an announcement at a separate event on Tuesday, saying that he supports a path to citizenship for young undocumented immigrants. Speaking at the American Enterprise Institute, House Majority Leader Eric Cantor said "a good place to start is with the kids."

The hearing continued in the afternoon with testimony from several think tanks, as well as a Julie Myers Wood, a former assistant secretary for U.S. Immigration and Customs Enforcement (ICE).